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(1) CHE 201, Organic chemistry I
(2) CHE 202, Organic Chemistry II
(3) CHE 201, Organic Chemistry I, Hybrid course on line
(4) FOS 402 Undergraduate Research Internship
Current research interest:
Mitomycin C chemistry
We are interested in the synthesis of mitomycin C-DNA adducts. Mitomycin C ( MC1), an antitumor antibiotic, is used in clinical cancer chemotherapy.2 Its cytotoxic and antitumor activity is attributed to its ability to alkylate DNA monofunctionally and bifunctionally, the latter mode resulting in DNA interstrand and intrastrand cross-links3. Six major DNA adducts have been isolated from in vitro systems, formed under biomimetic conditions, and their structures have been elucidated4, including the DNA interstrand cross-link 3a (ICL), the first such adduct of a natural antibiotic5 (see chart). The same six DNA adducts were shown to form in tumor cells treated with MC6. The ICL was also isolated from rat liver DNA of animals injected with the drug5. The structures of the six MC-DNA adducts illustrate that the exclusive target of alkylation of DNA by MC is the guanine base. Individual structure-activity relationships of multiple DNA adducts generated by a single agent have been investigated mostly in the case of organic mutagens and carcinogens7. In general, such studies utilize synthetic oligonucleotides bearing a specific adduct at a unique position of their base sequences. The MC adducts present an opportunity for similar studies, enabling in this case direct comparisons of biological effects of the various DNA adducts of a cancer chemotherapeutic agent. Synthesis of most of the six MC adducts incorporated in oligonucleotides has been accomplished by the biomimetic route, consisting of the alkylation reaction of MC with a short DNA duplex of appropriate sequence in the presence of a reductive MC-activating agent. Varying the activation conditions leads to different adducts8. This approach has been successfully applied in the case of most adducts 9,10,11. However, the method is usually inefficient, due to the difficulty of purification of the product to homogeneity. Furthermore, adducts 1b and 6 are formed in very low yield by the biomimetic approach to be practical.
We reported the first alternative access to one of the adducts of MC, based on organic synthetic methods, featuring a postoligomerization approach12a,b in which the normal nucleophile-electrophile relationship of the DNA nucleoside and the drug is reversed by using an amine derivative of the latter and 2-fluorodeoxyinosine as the DNA target site. Specifically, we described a synthesis of monoadduct 6 13 on both the nucleoside and oligonucleotide levels. This synthetic approach to the previously unavailable sister adduct 6 will provide a substrate to examine the biological and structural properties of 6 in parallel with its major groove adduct counterpart 5. It will also be interesting to compare properties of 6 with those of the other minor groove guanine-N2 adducts of MC, 1b and 4. Our next target is to find a synthetic route to the novel stereo-isomeric DNA adducts (beta adducts 2b and 3b) that result from Decarbamoyl Mitomycin C treatment of cells.
It was found that DMC is able to rapidly induce cell death in the absence of wild-type p53 protein function and the markers seen during this cell death have features replication-stress induced death14, the programmed necrosis pathway15, and may even be caused by autophagy as this is an efficient p53-independent cell death pathway16. One long-term goal of is to determine the p53-independent signaling pathway(s) activated by DMC as a means to identify molecular targets for killing cancer cells by non apoptotic death pathways.
In order to gain insight into the damage signaling pathway, we want to determine the set of sensor proteins which bind to the synthetic MC and DMC-adducts in the presence or absence of p53. It has previously been shown that the damage induced by the two drugs signals to different death pathways in the presence and absence of p53, suggesting that the DNA-adducts serve as sensors.
We also want to identify which cellular proteins (from untreated cells, or MC or DMC treated cells) are recruited by the synthetic lesion and non-lesion oligonucleotides. The nuclear extract derived from the treated and untreated human cancer cells will be compared for the ability of their proteins to bind to DNA by gel shift experiments. A comparative analysis of each nuclear extract with the specific adducts will allow us to determine if specific factors have the capacity to bind to the altered stereochemistry and if DNA damage is required to activate binding to the synthetic lesion. If variable binding is determined for the different adducts, then experiments will be carried out to determine the identities of the protein products.
(1) Abbreviations: MC, mitomycin C; DAM, diaminomitosene; ICL, interstrand cross-link.
(2) Verveij, J. D. H.; Pinedo, H. M. In: Cancer Chemotherapy, Chabner, B. A.; Collins, J. M., Eds; Lippincott; Philadelphia, PA, 1990; pp. 382-396.
(3) Tomasz, M. Chem. Biol. 1995, 2, 575-579.
(4) Palom, Y.; Belcourt, M. F.; Musser, S. M.; Sartorelli, A. C.; Rockwell, S.; Tomasz, M. Chem. Res. Toxicol. 2000, 13, 479-488.
(5) Tomasz, M.; Lipman, R.; Chowdary, P.; Pawlak, J.; Verdine, G. L.; Nakanishi, K. Science 1987, 235, 1204-1208.
(6) Bizanek, R.; Chowdary, D.; Arai, H.; Kasai, M.; Hughes, C. S.; Sartorelli A. C., Rockwell, S.; Tomasz, M. Cancer Res. 1993, 53, 5127-5134.
(7) Basu, A. K.; Essigmann, J. M. Mutation Res. 1990, 233, 189-201.
(8) Tomasz, M.; Palom, Y. Pharmacol. Ther. 1997, 76, 73-87.
(9) Kumar, S.; Lipman, R.; Tomasz, M. Biochemistry 1992, 31, 1399-1407.
(10) Borowy-Borowsky, H.; Lipman, R.; Tomasz, M. Biochemistry 1990, 29, 2999-3006.
(11) Suresh Kumar, G.; Musser, S. M.; Cummings, J.; Tomasz, M. J. Am. Chem. Soc. 1996, 118, 9209-9217.
(12) a) DeCorte, B. L.; Tsarouhtsis, D.; Kuchimanchi, S.; Cooper, M. D.; Horton, P.; Harris, C. M.; Harris, T. M. Chem. Res. Toxicol. 1996, 9, 630-637. b) Cao, H.; Jiang, Y.; Wang, Y. J. Am. Chem. Soc. 2007, 129, 12123-1230.
(13) Champeil, E., Paz, M.; Ladwa, S.; Clement, C.; Zatorski, A.; Tomasz, M. J. Am. Chem. Soc., 2008, 130, 9556–9565.
(14) Zhang, Y.W.; Otterness, D.M.; Chiang, G.G.; Xie, W.; Liu, Y.C.; Mercurio, F.; Abraham, R.T. Molecular cell 2005,19, 607-618.
(15) Zong, W.X.; Thompson, C.B. Genes & development 2006, 20, 1-15.
(16) Nelson, D.A.; White, E. Genes & development 2004, 18, 1223-1226.
Among promissing nanoparticles, fullerene C60 is particularly interesting in the field of medicinal chemistry due to its hydrophobic nature and unique shape. In the context of a search of new fullerene-containing chemotherapeutic agents, we already have synthesized a series of C60-derived building blocks characterized by the presence of functional groups linked to the C60 backbone by a flexible tether of variable length. We selected organometallic reagents carrying orthoester, acetal and silylether functional groups as precursors for carboxylic acids, aldehydes and alcohols respectively1.
Our goal is to synthesize molecules which will be more efficient chemotherapeutic agents than Mitomycin C. By linking MC to fullerene C60, we want to increase the tumor cells targeting capability of MC and we want to increase the cellular drug uptake and the DNA alkylation. We strongly believe that the cellular drug uptake will be increased due to the presence of the fullerenyl moiety as there is literature precedence of such a phenomenon. Recently, Barron et al. have described a general approach to the formation of a fullerene-containing cell-penetrating peptide. By linking their fullerenyl amino-acid to a cationic peptide, a prompt delivery of both the peptide and the fullerene components inside the cell membrane was allowed whereas the peptide on its own could not enter the cell2.
They concluded that the fullerene moiety enabled the transport into cells of the peptide. Furthermore, the authors noticed that these fullerenyl peptides were located in the nucleus region of the cells. The fact that the cell uptake of their fullerenyl peptide was found to be temperature dependant suggested that the cellular uptake activity was an endocytosis process promoted by the hydrophobic nature of the fullerene. They concluded that the hydrophobic fullerene in combination with the hydrophilic peptide sequence may form an amphipatic cell penetrating peptide.
We want to synthesize molecules with a fullerene-alkylchain-MC skeleton which will form amphipatic cell penetrating structures. The hydrophobic moiety being the fullerene C60 and the hydrophilic being the mytomicin structure. A cross section of the macro structures that can be formed with our amphipatic molecules is represented below. The white sphere represents the fullerene moiety, the orange fragment, the alkyl chain and the mitomycin moiety.
(1) Champeil, E.; Crean, C.; Larraya, C.; Pescitelli, G.; Proni, G.; Ghosez, L Tetrahedron 2008, 64, 10319–10330.
(2) a) Yang, J; Alemany, L. B.; Driver, J.; Hartgerink, J. D.; Barron, A. R. Chem. Eur. J. 2007, 13, 2530-2545. b) Yang, J.; Wang, K.; Driver, J.; Yang J.; Barron, A.R. Org. Biomol. Chem. 2007, 5, 260-266.
Drug of abuse characterization in human fluids
Recently we started to investigate the possibility of characterizing the presence of Drugs of abuse in human fluids using NMR spectroscopy. Below is a typical spectrum of a urine sample after ingestion of 3,4-methylenedioxy-N-methylamphetamine (MDMA, ecstasy). Superimposed in gray is the spectrum of MDMA spiked urine (0.50 mg/mL). Characteristic peaks of the drugs are clearly visible. These results suggest the 1H NMR spectroscopy could provide a convenient tool for the rapid detection of MDMA in human urine.
This method presents the advantage of a rapid diagnosis with little of urine needed and no sample preparation. Furthermore, in the concentration range studied, quantitative data can be collected and samples were analyzed within 20-30 minutes. In an emergency clinical context, the diagnosis problem could be at least partially solved if a rapid identification procedure was available. The NMR method should be useful in rapidly confirming the diagnosis of poisoning.
Of course, all this would not be possible without the contribution of these wonderful John Jay Students:
Elaan Luckaziewitcz, Kyle Zavinsky, Samantha Sellers, Stephanie Watson, Sandy Kong, Jonathan Liu, Casey Lesar
Selected Recent Publications
●Elise Champeil, Gloria Proni, Danielle Sapse, “Ab Initio studies of receptor interactions with AMPA ((S)-2-amino-3-(3-hydroxy-5-methyl-4-isoxazolyl) propionic acid ) and kainic acid (2S-(2α,3β,4β))-2-carboxy-4-(1-methylethenyl)-3-pyrrolidineacetic acid”, Journal of Molecular Modeling 15 (2009): 1109.
●Elise Champeil, Conor Crean, Carlos Larraya, Gennaro Pescitelli, Gloria Proni , Léon Ghosez, “Functionalization of C60 via organometallic reagents”, Tetrahedron 64 (2008): 10319.
●Manuel M. Paz, Sweta Ladwa, Elise Champeil, Li-Quian Tang, Sara Rockwell, Ernest Boamah, Jill Bargonetti-Chavarria, John Callahan, John Roach, Maria Tomasz, “Mapping DNA adducts of mitomycin C and decarbamoyl mitomycin C in cell lines using liquid chromatography/ electrospray tandem mass spectrometry”, Chemical Research in Toxicology 21 (2008): 2370.
● Danielle S. Sapse, Elise Champeil, Jacques Maddaluno, Catherine Fressigné, Anne-Marie Sapse, “Ab initio study of the interaction of DNA fragments with methyllithium”, Compte rendu des Séances de l’Académie Francaise 11 (2008): 1262.
● Elise Champeil, Manuel Paz, Sweta Ladwa, Cristina Clement C, Andrzej Zatorski
, Maria Tomasz, “Synthesis of an
oligodeoxyribonucleotide adduct of mitomycin C by the postoligomerization
method via a triamino mitosene”, Journal
of American Society 130 (2008): 9556.
● Elise Champeil, Padmanava Pradhan, Mahesh K. Lakshman, “Palladium-catalyzed synthesis of nucleoside adducts from bay and fjord region diol epoxides”, Journal of Organic Chemistry 72 (2007): 5035.